Apparatus for decelerating torpedoes



Jan. 30, 1951 w. R. SMYTHE 2,539,643

APPARATUS FOR DECELERATING TOBPEDQES I 4 Sheets-Sheet 1 Filed May 8,1946 INVENTOR WILLIAM R. SMYTHE Jan. 30, 1951 w, R, sMYTH 2,539,643 7APPARATUS FOR DECELERATING TORPEDOES Filed May 8, 1946 4 Sheets-Sheet 2INVENTOR WILLIAM R. .SMYTHE ATTORNEY n. 30, .951 w. R. SMYTHE 2,

APPARATUS FOR DECELERATING TORPEDOES,

Filed May 8, 1946 4 Sheets-Sheet s SMYTHE ATTORNEY Patented 30, 1951APPARATUS FOR DECELERATIN G TORPEDOES William R. Smythe, Sierra, Madre,Calif., assignor to the United States of America as represented by theSecretary of the Navy Application May 8, 1946, Serial No. 668,027

6 Claims. (01. 114-20) This invention relates to apparatus fordecelcrating torpedoes, that is, to apparatus for reducing the forwardvelocity of a torpedo so that it may enter the water without damage whenlaunched at high altitude or from a fast moving airplane.

One object of the present invention is to provide an apparatus fordecelerating torpedoes, which'employs rocket motors mounted around thetorpedo body with their discharge jets directed forwardly parallel tothe axis of the torpedo.

Another object of the invention resides in the provision of an Iapparatusv 'of this character which is automatically thrown clear of thetorpedo after eflecting the desired deceleration and before the torpedostrikes the water.

Another object is to provide an apparatus of this character which may bereadily installed on conventional torpedoes and in no manner interfereswith the normal operation thereof.

A further object of the invention is to provide a torpedo decelerationapparatus in which the decelerating force is produced by rocket motors,and which includes altimer for initiating operation of the rocket motorsafter the torpedo is dropped and then initiating operation ofmechspectively, of the discarding mechanism which initially joins thetwo deceleration units;

Fig. 8 is a side view, partly in section, of one of the timers forcontrolling operation of the rocket motors and the discarding mechanism,with the timer cover removed;

Fig. 9 is a sectional view on the line 99 in Fig. 8, but with the coverin place, and

Figs. 10 and 11 are sectional views on lines IIIII| and III I,respectively, in Fig. 9. l The deceleration apparatus, as illustrated,comprises a pair of deceleration units encircling a torpedo A near itsrear end. Each deceleration unit employs a plurality of rocket motorsIII having propellant grains II, each motor being disposed with its axisparallel to the torpedo axis and having its nozzle or discharge end Illadirected toward the front end of the torpedo. The rocket motors I0 maybe conventional and may be internally similar to the rocket motordisclosed in a copending application of C. C. Lauritsen, Ser. No.481,645, filed Apr. 2, 1943,

'for Rocket Device now Patent No. 2,469,350.

anism for throwing the deceleration apparatus 1' clear of the torpedobefore the latter strikes the .water.

An additional object is to provide a timer of the character describedwhich is 50 arranged that the timing period between ignition of therocket motors and operation of the mechanism for throwing thedeceleration apparatus clear of the torpedo varies with' change intemperature at virtually the same rate that the burning periods of therocket motors vary; that is, to provide a timer which automaticallyshortens or lengthens its time interval in accordance with the changesin burning time of the rocket motors insofar as such changes are due tochanges in temperature.

- These and other objects of the invention may be better understood byreference to the accoms panying drawings, in which:

Fig. 1 is a side view of a torpedo having one form of the newdeceleration apparatus, showing the torpedo in flight during operationof the apparatus; I

Fig. 2 is an enlarged side -view of part of the torpedo, showing thedeceleration apparatus thereon;

Figs. 3, 4 and 5 are sectional views on the lines 3-3, 4-4 and 55,respectively, in Fig. 2;

Figs. 6 and 7 are detail side and top views, re-

The bomb case illustrated in said copending application is, of course,omitted and caps I2 substituted; The caps I2 are threaded or otherwisesecured to the motor tubes In at their front ends, which are directedtoward the rear end of the torpedo.

The tube of each rocket motor I0 is modified to fit closely in' a nozzleend yoke I3, an intermediate yoke I4 and a spacer cleat I5. One nozzleend yoke I3 is provided for each deceleration unit, each yoke being inthe form of an arcuate plate having holes which receive the nozzle endsIlla of the rocket motors comprising the unit. There is also oneintermediate yoke I4 for each set of rocket motors, each intermediateyoke being in the form of an arcuate plate having semicircular,peripheral recesses which receive the rocket motors. Retaining wedges I6are inserted between adjacent rocket motors I0 and secured to the outeredge of the intermediate yoke I4, as by means of screws Ilia. As shown,each motor tube II] has spaced shoulders IOb between which theintermediate yoke I4 and adjacent wedges I6 are received. Also, thenozzle end portion Illa of each motor tube has a shoulder I00 engagingthe outer face of the yoke I3.

The after body B of the torpedo, at the point opposite the rear orcapped ends I2 of the rocket motors, is not truly cylindrical in crosssection. Consequently, the spacer cleats I5 are made adjustableradially, as shown in Fig. 5. The yokes I3 and I4 and the spacer cleatsI5 are arranged rocket motors parallel to the longitudinal axis of thetorpedo. The intermediate yokes I4 transmit thethrust of the rocketmotors to the torpedo from the shoulders lllb, suitable means beingprovided to secure the yokes lkand the torpedc against relativelongitudinal movement. For example, the intermediate yokes ma haveprojections |4a (Fig. 3) which flt into the usual bolt recesses |1provided in the after body B to receive the bolts for connecting theafter body B to the main body A of the torpedo; or these connectingbolts (not shown) may hold suitable lugs engaging the yokes l4.

As shown, each deceleration unit employs six rocket motors l0, althoughmy other desired number of motors may be used. The two units are joinedby two identical discarding mechanism i8 shown assembled in Figs. 2. 6and 7. Each discarding mechanism l8 comprises a socket member Ian and a,mating piston member I9 which are initially held together by shear bolts29. .The socket member is adapted to contain a small charge of powderadapted to be ignited by that the explosive pressures are substantiallyrelieved before the piston member I9 is fully'ejected from the socketmember by explosion of the powder charge therein.

Each discarding mechanism I8 is joined by 'flexible links 23, 23a to theadjacent end portions of the intermediate yoke l4 of the twodeceleration units. One of these links may include an adjustable andseparable connection 24 so that the two deceleration units may bereadily secured to or removed from the torpedo.

The deceleration units are each provided with a timer 25 which controlscurrent supplied by batteries 25 supported across the capped ends l2 ofthe rocket motors. Each timer 25 is mounted on a suitable bracket 21secured to one of the spacer cleats l5 of the corresponding decelerationunit. The timers 25 are identical in construction, so that a descriptionof one of them will sumce.

The timer is contained in a housing comprising a flat base plate 32 anda cover 33 shaped to accommodate the timing mechanism therein. Withinthe housing and extending with its axis parallel to the base plate 32 isa cylindrical shell 34 having a partition 35 at one end and open at itsother end. Within the shell is a latch carrier 35 in the form of a tubespaced from the shell 34. The latch carrier is provided with an internalflange 31 at its inner end which confronts the partition 35, and anexternal flange 33 at its other or outer end. A coil compression spring39 surrounds the latch carrier 36 between the flange 39 and thepartition 35 so as to urge the internal flange 31 away from thepartition 35. I

The partition 35 is provided with a slot 40 which extends across thepartition 35 parallel to The latch plate 4| is adapted to restrain thetoggle arms 44 and 45 of toggle switches 46 and 41, as will be describedin more detail hereinafter.

The toggle switches are supported by a bracket midway between theextremities of the latch car-' .rier 35 and isprovided with a plug 5|threaded therein.

Bellows 53 and 54 of the s'ylphon type are secured to the faces of plug5| and extend in opposite directions therefrom. The forward bellows 53is secured to an end fltting 53a which in turn issecured to the disk 4|awhich supports the :latch plate 4|.

A stem 55 is secured to the end fitting 53a and extends through the plug5| to another end fitting 54a secured to the extremity of the rearbellows 54. The bellows 53 and 54, together with their end fittings 53aand 54a and the plug 5|, define respectively a forward chamber 51 and arearward chamber 58. The'chambers are filled with a damping liquid andthe clearance between the stem 55 and plug 5| is such that the fiow,oithe liquid between the two chambers 51 and 58 is restricted so that thelatch 4| moves slowly under urge of the spring 39.

Toluene serves admirably as a damping liquid for use with thedeceleration apparatus, for the reason that its viscosity decreases withtemperature at nearly the same rate as the burning time of the rocketmotors I0.

A reel cage 59 is secured to the bottom of base plate 32 and supports areel drum'fill. A hollow journal 5| is secured to the base plate 32 forsupporting the inboard side of the reel drum 59, while the outboard sideof the drum 59 has a boss 52 which is journaled in the cage 59.

The journal stem 5| is internally threaded and registers axially with ahole 63 extending through the partition 35. A latch pin 94 is slidablein the hole 63 and normally extends through a mating hole in the latchplate 4|. The intermediate portion of the latch pin 64 is threaded, asshown at 64a, to mate with the threads in the journal stem 6|, sothat-the latch pin is moved axially when it is rotated. The outer endportion of the latch pin 64 is slotted, as indicated at 65, and extendsthrough a central opening in the boss 62. A cross pin 65 fits into theslots 65 and extends through the reel boss 52 so as to rotate the latchpin when the reel drum 50 is rotated. I

A lanyard 51 is removably attached at one end to the reel drum 69 and isadapted to be wrapped about the drum several times so that when the freeend of the lanyard is pulled, the drum is rotated sufllcicntly towithdraw the latch pin 64 from the latch 4|, whereby the latch is movedclear of the toggle arms 44 and 45 by means of the spring 39 asrestrained by the fluid in the chambers 51 and 58. The free end oflanyard 51 extends through a slot 59a (Fig. 11) in cage 59 and issuitably connected to' the airplane, so that when the torpedo isreleased the lanyard is unwound from reel 60, thereby rotating the reeland withdrawing latch pin 54.

Springs 58 are attached to the toggle arms 44 and 45 and anchored to thebase plate 32 so as to snap the switches from one position to another assoon as the latchplate 4| clears the toggle arms. The toggle switches 45and 41 are preferably mounted-in the bracket by means oi adjustableconnections 68, and the edge of the latch plate 4| may be stepped at aso that one toggle arm is released before-the other. The intervalbetween release of the toggle arms is, of course, dependent upon theviscosity of the damping fluid.

Jacent timer, and wiring 12 and 12a to the normally closed switches 46and 41, respectively.

Extending from each plug and socket connector II are parallelconnections 13 and 13a, the connection 13 leading to the usuale.ectrical igniters of the parallel connected rockets iii of thecorresponding deceleration unit, and the other connection 130 lead.ng tothe igniters of the rockets of the other deceleration unit. The switch41 in eachtimer 25 is connected by wiring 14, in parallel with wiring12a, to a plug and socket .connector 15 on the timer. Branch connections18 and 16a extend from each connector 15, the connection 16 leading toone of the ignltion plugs 2| on the corresponding side of the torpedo,and the other connection 18a leading to one of the ignition plugs 2| onthe opposite side of the torpedo. The wiring I3, 13a is connected to therocket igniters through conductors 11 extending through the nozzle endsIlla of the rocket motors.

From the foregomg, it will be seen that the toggle switch 46 of eachtimer is adapted to complete the circuits from the batteries 26 to allof the rocket motors i0, and the other switch 41 is adapted to completethe circuits to the electric igniter plugs 2| of the connecting means18. The toggle switches are preferably arranged so that they short theelectrical igniters in the rocket motors and the igniter plugs 2|, whenthe toggle switches are in their initial positions shown in Figs. 8 and9, to minimize the possibility of accidental ignition.

The lanyards 61, which are connected to the airplane, must unwind fromtheir respective drums 60 upon release of the torpedo, before the robketmotor switches 46 are released. Thus, the rocket motors are not igniteduntil the torpedo is a safe distance from the airplane.

The propellant ll contained in the rocket motors has a burning speedwhich varies with temperature. It is desirable that the rocket motorscomplete their burning period before the deceleration units are thrownclear of the torpedo. In order to insure this, the damping fluid chosenfor filling the bellows 53, 54, namely toluene, varies in viscosity atnearly the same rate as the variation in burning speed. The intervalbetween operations of the two toggle switches 46, 41 should exceed theburning period of the rocket motors by approximately 25 per cent; Theburning period of one type of rocket motor varies from 0.2 second to 0.8second; consequently the timer used in conjunction with this motorshou.d vary from about 0.3 to 1.0 second within the same temperaturerange as that considered for the burning time of the rocket motor.

a 6 In order tofacilitate complete separation of the conductors whichjoin the two deceleration units, one or the discarding mechanisms it maybe provided with a conduit shearing means 80,

as shown in Figs. 2, 6 and 7. v This comprises mating holes in one ofthe socket members Ila and its piston it, through which extends aconduit 8|, preferably of plastic material, carrying the necessaryconductors.

Operation of the deceleration apparatus is as follows. The twodeceleration units are secured around the torpedo A by the two sets ofconnections it, 23 and 24, the connection between the after body and theforward body of the torpedo cooperating with the projections Ma on yokesH to secure the units against longitudinal movement on the torpedo. Thenozzle ends Illa of the rocket motors are directed toward the forwardend of the torpedo so that the thrust of the rocket motors is directedrearwardly in opposition of the forward travel of the torpedo. Thewiring is then connected as described.

When the torpedo is launched, the lanyards 61 rotate the drums 60,- sothat the latch pins 64 are withdrawn from latch plates 4i after thetorpedo has cleared the airplane a safe distance. The springs 39 thenmove the latch plates 4| outwardly against the restraining force of theliquid in bellows or dashpot 53, 54, whereby the switches 46 and 41 areoperated in timed sequence. When the first switch 46 is operated,rocket'motors ID are ignited and their resulting action creates asubstantial backward thrust to slow the forward velocity of the torpedo.Experimentation indicates that twelve rocket motors, of the typedisclosed in said copending application Ser. No. 481,645, give a totalthrust of fifteen tons lasting approximately a half a second, which issuflicient to reduce the speed of a one ton torpedo by 120 knots.

the rocket motors l0, approximately three-fourths to one second, thesecond switch 41 is operated to close the circuits to the squibs (notshown) 45 connected with the ignition plugs 2 I, causing the powdercharges within the discarding mecha* nisms l8 to separate the pistonmembers l9 from their socket members lBa with sumcient force to throwthe two deceleration units clear of the torpedo. In the operation of thediscarding mechanisms 18, the shearing device 80 shears the cable 8! byaction of the piston i9, thereby facilitating separation of thedeceleration units from the torpedo.

I claim:

' water-borne torpedo, a torpedo decelerating apparatus comprising apair of arcuately shaped supporting yokes, explosively actuated meansinitially connecting said yokes together at their extremities to form aband encompassing the torpedo body and adapted when actuated to separatesaid yokes, rocket motors carried by said yokes. and a timing device forigniting said rocket g5 motors and thereafter actuating said connectingmeans. whereby said rocket motors and their yokes are thrown clear ofsaid torpedo.

2. A torpedo decelerating apparatus comprising a pair of rocketsupporting yokes adapted to be 7 mounted on a torpedo, a pair ofseparable links connecting said yokes at their extremities to form aband around the torpedo, at least one of said links comprising a pistonand a socket member defining a chamber for receiving an explosive 1;which when ignited drives said piston and socket After the intervalrequired for the operation of 1. In combination with anaircraft-launched,

with an aircraft-launched,

connecting means Joining said supporting devices to form a band aroundthe torpedo body and hold said rocket motors with their discharge endsdirected forwardly and generally parallel to the torpedo axis, each ofsaid separable connecting means including piston and socket elementsdefining a chamber for an explosive'charge adapted when ignited tothrust said elements apart, thereby to throw said supporting devices andtheir rocket motors clear of said torpedo body, and a shear deviceinitially restraining said piston and socket elements.

4. In combination with an aircraft-launched, water-borne torpedo, atorpedo decelerating apparatus comprising apair of decelerating unitseach including an arcuate supporting device conforming to the torpedobody and a plurality of rocket motors carried by said device, separableconnecting means joining said supporting devices to form a band aroundthe torpedo body and hold said rocket motors with their discharge endsdirected forwardly and generally parallel to the axis of said torpedo,each of said separable connecting means including piston and socketelements defining a chamber for an explosive charge adapted when ignitedto thrust said elements apart, thereby to throw said supporting devicesand their rocket motors clear of said torpedo body, a shear deviceinitially restraining said piston and socket elements, and a timingdevicefor initiating operation of said rockets to effect deceleration ofsaid torpedo body and thereafter operating said connecting means toefiect separation of said supporting devices and their rocket motorsfrom the torpedo body,

5. In a torpedo deceleration apparatus having a plurality ofelectrically fired rocket motors, a discarding mechanism for throwingthe deceleration apparatus clear of the torpedo and adapted to be 8started electrically, and a source of electrical energy, a timermechanism comprising a pair 01 switches for controlling the supply of'energyi'rom said source to said rocket motors and said discardingmechanism, respectively, latch means restraining said switches andmovable to release said switches in sequence, a spring urging said latchmeans free of said switches, a dashpot for controlling the rate ofmovement of said latch under urge of said spring thereby to control theinterval between release of said switches, a pin initially restrainingsaid latch, a drum, means connecting said drum with said pin to withdrawsaid pin from said latch upon rotation of said drum, and a lanyard forrotating said drum.

6. A timer mechanism comprising a hollow, cylinder closed at one end, alatch carrier mounted in the cylinder, a compression spring coiledaround the carrier within the cylinder for urging the carrier toward theopen end of the cylinder, 9. dashpot for restraining movement of thecarrier by the spring, a latch on the carrier extending through theclosed end of the cylinder, a pair of switches, biasing means foroperating the switches, the latch normally holding the switches againstoperation by the biasing means and being movable by the spring torelease the switches in sequence, a latch pin movable in the cylinderand normally locking the latch against movement, a drum connected to thepin and rotatable to withdraw the pin from the latch and thereby releasethe latch, and a lanyard wound around the drum for rotating the same.

' WILLIAM R.- SMYTHE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS I Date

